Bruce roberts official web site powerboat plans power boat kits for steel boats or aluminum boat designs, cut to size boat kits, part built boats or complete boats.. Coastal motor boat. during world war i, the british royal navy needed a small, inconspicuous combat vessel with the ability to sneak up on enemy german ships anchored. Boatplans.dk – online free and inexpensive boat plans for canoes, small boats, sail boats, motorboats and powerboats. download boat plans right away. – boatplans.dk.